How to Kill Bahai Grass

Choose a type or pre-emergent herbicide that not only says on the label it prevents the germination of Bahia grass seed, but will not kill the type of desirable lawn grass you are growing. For example, atrazine is appropriate for use in St. Augustine grass and centipede grass, but will kill or weaken other turf grasses. Also, it must be applied at the correct time in the spring before the Bahia grass seed sprouts. A pre-emergent herbicide is applied specifically to prevent weed seeds from germinating and must be applied several times during the growing season. It will not kill existing Bahia grass clumps.

For pre-emergent herbicide recommendations, contact your local county agricultural extension office. They will have a list of approved pre-emergent herbicides to control Bahia grass along with the suggested times for application. Your county extension office is the only reliable source for this information.

Mix a liquid pre-emergent herbicide in a garden sprayer or fill a lawn spreader adjusted to the correct spreader setting if you are using a granular product. Apply over the surface of the affected area at the correct concentration and right time of year according to the information from your county extension office. This will normally be done in the spring before the existing clumps of Bahia grass begin to turn green.

Mix the correct amount of herbicide containing glyphosate, the active ingredient in Roundup weed killer, in a garden sprayer after the Bahia grass clumps turn green in spring and before the seed heads appear. There are several different concentrations of glyphosate available on the market, so follow directions carefully while mixing.

Spray the individual clumps of Bahia grass in the lawn with the glyphosate mixture. Glyphosate will kill any other grass it contacts, so use caution and do not spray on a windy day. Be sure to cover the leaves of each clump of Bahia grass with the herbicide. A second application may be necessary if the Bahia grass is not dead after two weeks.